This invention relates to a shuttle for providing an intermittent drive motion to a work piece transfer member and more particularly to such a shuttle having a controlled acceleration and deceleration motion produced by a power means being rotated at a uniform rate of rotation.
Industrial shuttle mechanisms are employed to move a work piece transfer member in an intermittent motion. The shuttle mechanism employs a dog that is reciprocated in a forward direction to move the work piece transfer member in the same direction and then in the opposite direction to return the dog to its initial position to repeat the cycle with the next work piece transfer member. The dog is coupled to a rotary power means that is rotated in a uniform rate of speed through a 180.degree. arc during the drive motion and then rotated in the opposite direction to return the dog to its initial position. A cam is employed between the dog and the power means to change the rotating motion of the power means to a linear motion for the dog. At the beginning of the drive stroke, the dog is spaced from the work piece transfer member. The dog is then moved toward the work piece transfer member in an accelerating motion that produces a severe and noisy shock to the work piece transfer member as it is engaged in its stationary position by the dog.